Liberalize the naming of the articles (and categories? but absolutely not templates), and at the same time require that all localized (non-English) articles have the language suffix added to their title, be it translated or not, including redirects

Ideas

Ask Pierre to publish LocalSettings.php and include/require there the database connection data from another file, or vice versa publish a LocalSettings2.php that will be required in LocalSettings.php, where only the db connection data are stored (this can help hide the real location of the file with the connection data)

Templates should be coded so that they are language-neutral, with all their messages coded as {{{msg1|default English message}}}: non-English articles should use meta-templates that simply call the basic template localizing its messages: {{Template|msg1=localized message}}